just wondering.. is there a Google Hangouts app? (yes yes I know, why not use whatsapp instead? coz I have a diff group of friends that use hangouts)

currently using the android one and (unsure if its just me but..) this rarely ever updates...
for example.. ill open the app.. don't see any messages.. so I go into the group chat and I start typing, after a few minutes I will notice that there has been a convo happening for the last hour already!!!
and so I go and reply.. I sit there and wait for a response.. and never get a response

its only till almost another hour before the app 'refreshes' itself and then I can see everyones response to my message from an hour ago